When you pay for editing, shouldn’t you expect a perfect manuscript? In her blog post “Why Did the Editor Miss Errors in Your Book?” developmental editor Lisa Poisso notes that the accuracy of professional editors is generally quite high. Being human, though, any editor can miss something.

Experienced editors agree It’s fair to expect a copyeditor—those of us who focus on errors of punctuation, grammar, syntax, word choice, lack of clarity, and more—to catch at least 95% of the errors in a manuscript. Copyeditors worth their salt strive for perfection although, being mere mortals, we may have to live with a success rate of 99%.

The number of errors overlooked depends, in part, on the number of errors in the original. For example, in a book-length manuscript of 100,000 words, an editor may make 20,000 corrections. If that editor has an accuracy rate of 99%, there may have actually been 20,202 errors of which 202 were missed.

A cleaner manuscript will contain fewer errors and will need fewer corrections. How can you, the writer, produce a cleaner manuscript? Poisso’s post offers tips.